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1/5 Top Flight P-51 Electric

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Old 11-02-2008, 10:40 PM
  #1
Ron101
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Default 1/5 Top Flight P-51 Electric

I finally got all my little projects done and have started my P-51.
I'm doing the Top Flight 1/5 ARC. I year ago or so I did the ARF and sold it and really miss having it. I've been doing large electric jets and wanted to get back to my first true love in RC, the WARBIRD!!
Also after doing a 30% Dietrich extra 260 last Nov. with electric power and having more performance than a DA 50 I knew the P-51 would fly great on electric.
Today I got everything out of the box and checked the fit and finish. Top Flight has done a few improvements over the last one I had. First thing I noticed was the main wing joiner is now a solid hardwood block not laminated ply, it also fit very well. The last time I spent time sanding the joiner to get it to fit. Also the gear doors are much nice than the old ones. The main gear blocks look to be reinforced and glued really well. The formers on each side of the block are now tripled up... if I recall right they were just doubled before. I still plan to hit the area with thin CA then go over the weak areas with gorilla glue.

So here's the plan:
1. I went with the Spychalla cowl (what a work of art and great service, took about 10 minutes with the dremel to have a perfect fit thanks Leo)
This gives you the scale shape to the nose along with the right size spinner (5 1/2) also the scale air filter covers and the best part it molds in with no seam.

2. The motor is an AXI 5345-14 with a 21x14 prop and 12s 5000 mah (or 6000mah) packs. This is a real beast about an 80 cc gas motor. The Tru Turn 5 1/2 spinner is on order

3. Dynamic balsa cockpit, I used one on my last p-51 and they come out really nice. I will lighten it up for this plane. the armor plate is really heavy as is the batt. and radio. I'll make new ones from balsa

4. I'm going to glass it, add panel lines, rivets and paint it to be double trouble II; flown by Lt. Col. William B. Bailey of the 353 rd fighter group... mine will be a bit weathered not restored

5. Sierra Precision Gear with Glennis Wheels and the Robart tail retract

6. Also have the Tony Howard Exhaust on order

7. I'm going to make a hatch to access the batt. packs and switches I did this on a hanger 9 P-51 and it really makes it a joy to change the packs. I'll blend it into the panel lines

So that's the game plan. I don't think I'll post ever step unless there is a demand for it. I'm just going to have a lot of fun with it and try and get semi scale without going over board... and gaining to much weight. My target is 26 pounds and I'm pretty sure I can hit that. My last was 24.5 with no gas. But this will be glassed and painted.

Today I joined the wing, fixed some shipping damage on the fuselage (not to bad) fit the cowl and ordered a mess load of parts that will show up this week.
Here are a few pics.

Ron
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Old 11-03-2008, 12:20 AM
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Default RE: 1/5 Top Flight P-51 Electric

353rd - Very cool! looking forward to seeing it.
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Old 11-03-2008, 11:28 PM
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Default RE: 1/5 Top Flight P-51 Electric

A few guys have asked where I got my cowl from.. i got it from Leo Spychalla [leo@spychallaaircraft.com] just email him for price and wait time
well worth the wait and cost

Ron
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Old 11-04-2008, 12:10 AM
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Default RE: 1/5 Top Flight P-51 Electric

could you tell us how you decided on your electric setup? I would love to do an electric warbird, just not sure of the motor , speed controller and battery setup and cost. I and I am sure others would love to know the details. Down to your charger setup. Thanks
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Old 11-04-2008, 01:47 AM
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Default RE: 1/5 Top Flight P-51 Electric

Sure Ram-Bro I'll do my best.
I'm running the AXI 5345-14 this is on of AXI biggest out runners and has a high KV(rpm)
I choose this motor from searching the electric conversion on the other site.. also called hobby lobby and emailed AXI
Don (blade runner) used the 5345-16 with great results on his P-51
also most manufactures such as Hacker, Axi, Nue motor have charts to help give you and idea.. and call or email I find them to all really help out
here is a chart for the large AXI motors : http://www.hobby-lobby.com/brushless-axi5345.htm
once you have an idea of the motor you can use a program called moto calc to try different props and batteries to see how many amps you pull

For this setup I'll be using a castle creation 110hv, my setup should only pull 85 amps but this way I can prop up if I need more power
I'll be using two 6s 5000 pack in series to give me 12s 5000mah .. I may setup to 6000 mah if I want a longer flight time
just do a lot of research before you buy your setup. Researching a hot setup is part of the fun for me.

For charging my large packs I use two thunder power 1010 chargers with two 210 balancers hooked to a 50 amps power supply.
this way I can charge two packs at once. At the field I can fast charge in about 40 minutes. when I'm at home I just do a slow charge.
With four packs (two flight packs ) you can fly all day.. with throttle control I'll get 5:00 to 7:00 minute flights

Cost:
the Axi 5345-14 is $285
Castle creation 110 hv $269 so $554 total that’s cheaper than a zdz 80 which this power setup is very close to or the same cost of a DA 50

I look at the batteries as fuel.. I use the same packs for all my large planes some just one 6s 5000 some 12s
I have 4 of these packs and have put 50 flights on each.. you should get over 100 flights on these packs
I'm using thunder power packs each 6s 5000 pack is $300 .. ok so $1200 bucks sounds crazy but if I only get 100 flights per set
That works out to $6 a flight .. some of my older packs have gone well over 200 flights if the pack holds up well your talking $3.00 a flight that not to bad at all

Also I'm having really good luck with Hobby Cities Zippy packs which are half the cost of the thunder power.. I wouldn't use them in really high amp jet setups but work fine for warbirds
http://www.hobbycity.com/hobbycity/s...4&v=&sortlist=
The 6s 5000 mah are only $133 bucks keep the amps down (don't over prop) and you'll be good to go

it does cost a bit more.. but I just love electric.
no tuning, I've never had a dead stick since I converted my whole fleet two years ago, no mess
no fuel proofing needed, some think it's to quite but I hate the sound of weed whacker gas engines
More power... compared to nitro it's a no brainer (glow cost, mess, glow plugs, tuning, starting)
try it you'll love it!!
PM me if you ever need help with a settup
Ron

I added a picture of my charger settup
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Old 11-04-2008, 02:41 AM
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Default RE: 1/5 Top Flight P-51 Electric

Ron, good to see someone else going big electric. I looked at the cost of a twin gasser and the electric conversion and am looking at the electric as I already have the 6cell 5000 mAh batteries. The 85cc gasser is around $1100 AUD and the electric is around $200 AUD(HXT 80-100-b 130Kv) and around the same for the speed controller so a lot cheeper than the gas. I have been using the Zippy batteries and as long as you don't over load them they are a great battery at the price. Will be waching[sm=what_smile.gif]


Cheers
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Old 11-04-2008, 04:23 AM
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Default RE: 1/5 Top Flight P-51 Electric

Hey Ron, I've seen a finished T/F with Leo's cowl. Man What a difference his cowl makes vs stock. Then with Tony exhaust, that really tops it off. In fact, when I saw the plane ,I was almost afraid to ask if it was the T/F Mustang. Didn't want to insult him if had been an Aerotech.

I'm doing another Mustang this winter and I'm going to use the same parts. If I go with a D model I will also be doing the Double Trouble II scheme. (Gotta love Black and Yellow together) My Old Mustang is three years old now, I never knew a plane could last that long.
Kelly
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Old 11-04-2008, 10:01 AM
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Default RE: 1/5 Top Flight P-51 Electric

Thanks Ghost.. I've been making alot of coverters at the two clubs I fly at
I'm enjoying being the odd ball, because more and more electrics are showing up at the feild. It won't be long till it's the norm


Hey thunderbolt .. great to hear the cowl makes that big a differance, I'm so happy with it. Leo does a really nice job
Cool another double trouble.. it's hard to beat black and yellow


Also here are a few pics of my electric conversion ... all of them fly great
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Old 11-04-2008, 10:04 AM
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Default RE: 1/5 Top Flight P-51 Electric

few more...
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Old 11-04-2008, 10:09 AM
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Default RE: 1/5 Top Flight P-51 Electric

This is the ARF I did last year and sold... I'll be using the dynamic balsa cockpit kit again

sorry to get off track fo early..lol..just wanted to share a few pic... now back to the P-51 [&:]
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Old 11-06-2008, 01:23 AM
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Default RE: 1/5 Top Flight P-51 Electric

My Tony Howard exhust showed up today... really nice kit

man this with the new cowl is going to be really trick... I'll be hard at it this weekend [&:]

my motor showed up also.. still waiting on the mount and the tru turn spinner

I'll get somemore pics up the weekend

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Old 11-06-2008, 01:45 PM
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Default RE: 1/5 Top Flight P-51 Electric

Ron,

I am going to repeat a few installation steps here regarding the cowling and TH exhaust that you may not have seen but they could be helpful.


Mounting the cowling is very easy. There are 4 steps. 1) Check fit and sand to fit firewall as needed. 2. Align and drill your engine mount holes as it is easier to do this before mounting the cowl. I do this by standing the fuse on it's tail. 3) Epoxy bond the cowling permanently to the front of the plane. 4) Fill the gap with your favorite filler. I use Ultimate Bondo. More will be needed at the bottom on purpose. My goal was to help get a more scale line than TF had on there kit in this area.

Installation of the Tony-Howard exhaust requires 3 steps. 1) Sand the top end edge of the exhaust block down by about .040" to fit in the sockets I made to hold them. With a little work the standard set for the P-51 ARF can be made to fit just fine. 2) Cut away the balsa from the fuse to make a nice pocket for it. 3) Sand a notch in the back of the exhaust block to clear the fuse plywood. Do not clear away any of the plywood structure on the sides of the fuse because it will weaken the firewall. Create your clearance by sanding an angled step in the exhaust block. Leo
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Old 11-06-2008, 01:47 PM
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Default RE: 1/5 Top Flight P-51 Electric

Hey,

Good looking stuff, Ron!
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Old 11-06-2008, 11:01 PM
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Default RE: 1/5 Top Flight P-51 Electric

Thanks for the tips Leo...

Hey Shawn... Thank bud
good to hear from you

Ron
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Old 11-06-2008, 11:49 PM
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Default RE: 1/5 Top Flight P-51 Electric

Ron,

I have my TF wing glassed with all panel lines, rivets, and ready for flite metal. My fuse is almost glassed. I have added the spychalla cowl
too. I also added an Aerotech sliding canopy, gear doors and options kit. If you really want to deck out your mustang I highly recommend at least
get their sliding canopy before they quit making parts at the end of the year. It looks sooooo much better than the TF one. Installation really isn't that
big of a deal and with minor work it fits like a glove! Last time I talked to Wayne at Aerotech when I ordered mine he only had around 10 left and was
not going to make any more. I also like the scale options kit as well. It adds a lot of small needed details like the fuel caps, drop tank pylons, vortex
generators and my favorite - Scale guns. Either way you go it will look great. I just think with the work your putting in your plane you would be happier
with a few more upgrades. The only thing I did not do was relocate the Stab to scale location as I had already installed mine and I don't want to redo it.
The last thing I have to do is make the bulge in the bottom rear of the fuse leading up to and including the bottom of the rudder to give a more scale like
rudder appearance.
Any way good luck with your latest project.

Curt
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Old 11-07-2008, 01:45 PM
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Default RE: 1/5 Top Flight P-51 Electric

Hey Curt,
do you know if the aero tech inner gear doors fit the top flight gear doors?

how many hours do you think it took to add the sliding canopy.. did it take alot of filler?
I ask because I've read it's a PITA to fit right

Ron
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Old 11-07-2008, 08:09 PM
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Default RE: 1/5 Top Flight P-51 Electric

Ron,

I don't know if the Aerotech inners will fit TF I threw my TF away long ago so I cant match them up to tell you.

How hard it is to add the canopy really depends on your fabrication skill level. To me it was quite easy and worth it.
It took about 3 hours to build up the rear of the fuse where the canopy sits and to modify the top rear and install the rails
then about another half hour to glue the front canopy in place.

Here are some pics to show you. The fuse narrows towards the back of the canopy too much so I bent out the aluminum brace
in between the aerotech canopy frame out as much as possible that gave me about 1/4 inch then I built up the rear of the cockpit
sides with two pieces of 3/32 balsa sheet per side then sanded and blended to flow with the fuse and blend to the canopy.
Then cut the rear deck down add balsa sheet to the top. Cut groove for rear rail epoxy in place. Then add 1/4 inch square balsa
stock to inside of top of fuse wall for front rails to glue to. slide canopy frame on then glue canopy to frame while installed on Fuse.
Front canopy is easy just slide rear canopy so it is in the position you want it for the forward position. then glue front canopy and brace
in place against the rear canopy. I know that is a little hard to follow but if you decide to do it I will help answer any questions you have
more detailed. I will not have to add any filler except to the front canopy so it blends very smooth to the fuse. My pics look a little rough
but I havent sanded my fuse yet and still haven't finished all the glassing yet.
The epoxy you see in between the canopy frame and canopy will not be seen as soon as I flite metal the canopy. but it gives you an idea of
the shape compared to the TF canopy.

It isnt a great pic but I also threw in one of my wing.

Any questions ask away.

Curt
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Old 11-07-2008, 08:12 PM
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Default RE: 1/5 Top Flight P-51 Electric

I also forget to mention that the canopy fits very tight and straight against the fuse it is not wavy whatsoever.
The Aerotech canopy is also a lot thicker plastic than TF therefore more resistant to becoming deformed. The guys
at Aerotech make some quality stuff. I just wish I could have bought one of their mustangs before they quit making
them.
I think my TF mustang will look fairly decent when I get it done. I just need to get it done it is taking time away from
my Ziroli Stuka that I hope to get finished by spring.
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Old 11-08-2008, 05:45 PM
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Default RE: 1/5 Top Flight P-51 Electric

Hi Curt.

I am also making an electric conversion of the TF Mustang. I'm going to cover the whole bird in Flite Metal and paint it in a Royal Swedish Airforce livery (Yes, they bought a load of P 51's at the end of and after WWII)
I am also using the Aerotech sliding canopy, but haven't decided how to install it yet. Did you find your method reasonably easy? I have already built up the rear part to make the turtle-deck more scale and as a bonus the canopy fits spot on... According to Aerotech you are supposed to glue the front and rear part of the canopy in one piece and then cut them apart once the glue has set. I like your method better as I think it inhibits tension and misfit between the two canopy parts once separated. Mine will be fully functional, driven by a 4" air ram.
Any more pictures by any chance?

Cheers, Benny
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Old 11-08-2008, 08:25 PM
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Default RE: 1/5 Top Flight P-51 Electric

Benny,

I found my method fairly easy. I just felt more comfortable doing it in two pieces instead of one. One thing that I did was when gluing
the canopy on the frame I put it in traction with a lot of painters tape then layed the fuse on its side and put one piece of 1x2x12 balsa block
under the length of the canopy where the canopy meets the frame and another on the top of the fuse and applied weights on the top stick. I did
this to ensure the canopy glued the the frame in a manner that it would be flush with the fuse and have zero gaps. I used 30 minute epoxy.

Note in the pics how seamless the spychalla cowl is and how well the canopy fits against the fuselage. If you look in the pics behind the battery tray
I left part of the original fuse on the top deck I did this as a stop for the canopy in its forward position while I fitted and glued everything. I will soon remove
it and make the entire deck flat. And yes I made a boobo while sanding back and under the canopy on the fuse on one side that will require a little filler.

I still have to sand and fill and prime two more coats before the finish is in its final stage for panel lines and rivots. As well as finish fiberglassing the tail. So
my primer stage is still pretty rough.

Curt
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Old 11-08-2008, 10:04 PM
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Default RE: 1/5 Top Flight P-51 Electric

I love the idea of the canopy

but for now .. I'm going to go with out it.. I may change my mind before I glass it

but I want to keep it simple and light

Ron
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Old 11-09-2008, 02:01 AM
  #22
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Default RE: 1/5 Top Flight P-51 Electric

Ron,

Either way you go have fun. I would like to see some pics of your progress. I have never used electric before and was
planning on putting a DA-50 in my mustang but I am a big fan of keeping everything in the cowl for scale appearance.
With the mustang airframe it is hard so I would be open to electric. I do have a question with your electric setup.
Would it be possible to spin a scale sized 24 or 25 inch 4 blade prop with an electric motor or is that unfeasable. The only
way I can do that with the DA-50 is with a gear reduction setup.

Curt
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Old 11-09-2008, 06:10 AM
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Default RE: 1/5 Top Flight P-51 Electric

Curt.

I am using a 4-bladed, 24" scale prop from Soloprops. It has got ground adjustable pitch so you can experiment and get the perfect set-up. I'm using a Turnigy motor of 130 kV running on 4 6S 5000mAh LiPo's, to make 12S2P which will give 10000mAh and 44,4V. This set-up will give a quite low rpm (5772 rpm unloaded) but enormous torque to easily swing the big 4-blader. Pitch-setting will be high, around 16". Will try a 26-incher which the motor set-up will easily handle, but with a prop that size ground clearance will become an issue to seriously take into the calculation...
To make this machine seriously scale I am also using a Benedini soundsystem containing two light-weight (but very good sounding) speakers and a 2X40W ultra small amplifier. The actual sound unit with the pre-programmed Merlin engine sound is petite...
All this stuff of course adds extra weight, but one finesse with electric power of this size is that you still don't end up with a brick as long as you handle the throttle wisely at landings... Trying to keep everything else as light as possible, even gave my pilot som surgical treatment including lipo-suction... He's OK and, after all, I am medically trained [sm=wink_smile.gif]
There's a nice thread on electric conversion at
[link]http://www.rcuniverse.com/forum/m_2250626/mpage_1/key_/tm.htm[/link]
also check out [link]http://www.benedini.de[/link] I even think you have a retailer in the US for the Benedini-stuff...

Benny
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Old 11-09-2008, 08:40 AM
  #24
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Default RE: 1/5 Top Flight P-51 Electric

Benny,

I like to point out the inefficiencies that you will be dealing with when you change the pitch of the Soloprop up to 16" pitch. It is my understanding that the blades of the Soloprops are cut to a nominal 10" pitch. As we know that means that each rotation of this prop advances the airplane 10 inches in theory. Moving into the mathematics and trigonometry on this it then means that the tip of the blades at a 24" diameter travel a circumference of 75.4" in one rotation and the root near the 5.5" diameter spinner travels a circumference of 17.3". Stick with me here because it is worth it if you grasp this. In order to achieve efficiency at this 10" pitch the wooden blades are cut with an angle of 7.6 deg. at the tip and 30.0 deg. at the root (5.5" diam. spinner location).

(Cosine distance for the blade to travel is calculated as Pi X Dia. - Circumference. ex: 3.14 X 24 = 75.4 and 3.14 X 5.5 = 17.3. Use trigonometry to get the blade angle by taking the -TAN of 10" pitch (SIN) divided by 75.4 (COS) to get 7.6 deg.; and the -TAN of 10" pitch divided by 17.3 to get 30.0 deg.) This formula applies for any pitch you enter.

When you rotate those Soloprop blades to go to 16" pitch here is what happens. Let's say you rotate them to be 16" pitch at the tip. Thus -TAN of 16 / 75.4 is 11.9 deg. You will increase your angle from 7.6 deg. to 11.9 deg. at the tip or a 4.4 deg. increase to get your 16" pitch. At this time you also have increased your root pitch by 4.4 deg. or from 30.0 deg. to 34.4 deg. Working the trigonometry backward to find the root pitch you get TAN 34.4 X 17.3 = 11.8" Pitch. So you now have a 24" diameter 11.8 - 16.0 prop. The tips and the roots will be fighting each other at all power settings. When the tips are trying to advance 16 inches forward on each rotation the roots are only trying to move 11.8 inches forward. You can do this, but you will always lose efficiency versus a propeller that is cut with a 16" pitch blade both at the root and the tip. This would be 42.8 deg. and 11.98 deg. respectively.

Now some of you may say that Full Scale aircraft have constant speed variable pitch props and it works for them! So why not here? Well this is true and the same principles apply, however they cut there blades to have a constant pitch and efficiency at cruise. When they flatten the blades for low levels of thrust portions of the blade become inefficient.

On the pictures below I did a quick check of the pitch on a laminates 24 X 8 Xoar I have. What I measured is: 21.8 deg. root or 6.4" pitch root and 5.98 deg. tip or 7.9" pitch. So it lacks a little pitch at the root.

Leo
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Old 11-09-2008, 11:59 PM
  #25
turbo1
 
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Default RE: 1/5 Top Flight P-51 Electric

This is great,,,, hearing about the others......
I had my first flight on my P51E about a month ago,
dual 10cell A123 packs, 8120-5T Astro Monster 120, Castle Creations HV110 Speed Controller ...
and the same sound system on 8 cell nicad pack....
performance was ~~~~~ good,,,, finding out there were two week cells after landing,,,
now a set up to twin 12 cell packs will make this perfect... BUT,,,, 5" of snow will delay the next flight,,,,

next is a giant scale p63 on electric................
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